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638-642 Hayes St

Hayes Valley, SF 94102 0806008 3 units · 3 fl · 1890

This building has a higher-than-average number of open problems nearby. Few open issues; problems get fixed quickly. A reasonable bet for a smooth tenancy.

NOVs (7y) vs. neighborhood
Compared to a typical building in Hayes Valley
At or below average
avg 2.3
0
FewerMore

This building has 0 novs (7y), at or below the Hayes Valley average of 2.3.

Rent & eviction protection

Is 638-642 Hayes St rent-controlled?

San Francisco's Rent Ordinance caps rent increases and provides eviction protection for most residential units built before 1979 with 2+ units. Here's how this building scores.

Built before 1979
Built 1890
2 or more units
3 units
Property type
Multi-Family Residential
Zoning
RH3
Likely rent-controlled. Building age and unit count suggest this property falls under San Francisco's Rent Ordinance.

Based on SF Assessor records. Not legal advice — confirm with the SF Rent Board.

Building characteristics
Units3
Floors3
Year built1890
Total area3,770 sq ft
Property typeMulti-Family Residential
Tax statusNone
Blocklot0806008
Ownership

Registered owner per SF Assessor-Recorder (secured roll).

Owner name
Chang Daniel C
Mailing address
P O Box 2248 Alameda CA 94501
Last sale
022416

Landlord portfolio

Other SF properties this owner holds, with risk grades for each.

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Multiple entrances & addresses

Included addresses

All street addresses sharing this blocklot that are covered by this report.

640 Hayes St, San Francisco, CA 94102
638 Hayes St, San Francisco, CA 94102
642 Hayes St, San Francisco, CA 94102
Augrented Insights
Initial analysis

The three-unit apartment building at 638-642 Hayes Street in San Francisco's Hayes Valley neighborhood, owned by Daniel C. Chang, has a complex history with significant renovation activity concentrated between 2010-2016. Originally built in 1890, this three-story multi-family residential building underwent major improvements in 2010-2014 including a comprehensive renovation of all three units, installation of new fire alarm and sprinkler systems, complete rewiring, window replacements, bathroom and kitchen remodels, and HVAC upgrades with new furnaces and tankless water heaters. Notable improvements included a $379,900 project in 2010 to address numerous code violations including staircase repairs, bathroom additions, window replacements, and sprinkler system installation, as well as a 2014 fire alarm system upgrade costing $25,000. The building's electrical infrastructure was modernized with a 200-amp service installation in 2014.

The property experienced several significant regulatory challenges, particularly between 2007-2014, including multiple Notices of Violation (NOV) for unpermitted work, including illegal removal of interior finishes and unauthorized window replacements. These violations were primarily addressed through the substantial renovation work completed in 2010-2014. The building was listed as vacant or abandoned in 2012-2013 before restoration work resumed. Recent years have seen relatively few building-specific issues, though there have been recurring reports of sidewalk cleanliness concerns near the property, with multiple 311 calls in 2024 regarding debris and waste on the adjacent public street/sidewalk areas. The most recent major infrastructure work included a sewer line replacement in 2016, with various street space permits issued in recent years.

AI-generated · may contain errors · check the source data tables below

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Risk rating

How 638-642 Hayes St's risk score is calculated

We trained a model on 7 years of SF DBI inspection data — notice of violation filings, complaint history, and owner track records. It estimates the probability that DBI inspectors will issue a Notice of Violation at this address in the next 12 months. Lower % = safer.

What the score means for you

Grade A–B — Low risk

DBI rarely finds violations here. Strong maintenance history and a clean complaint record.

Grade C — Moderate risk

Some past violations or complaints on record. Worth asking the landlord about any open issues before signing.

Grade D–F — High risk

Elevated violation and complaint history. DBI has found issues here before and is statistically likely to again.

Neighborhood percentile
78th percentile

Out of 1027 buildings in this neighborhood, 226 are predicted to be safer.

RiskiestSafest
Predicted 12-month outcome
83%
No DBI
violation
17%
DBI violation
likely
Model explanation

What's driving this score

The three data points that most influenced this building's risk rating — ranked by the weight the model placed on each one.

Neighborhood (ZIP code)

The ZIP code captures local housing market and enforcement patterns that affect all buildings in the area.

Neighborhood location

Precise location is a proxy for neighborhood-level risk — some SF blocks have systematically higher DBI activity.

Estimated permit spend (past 7 years)

Dollar value of permits pulled at this address — large recent spend can signal deferred-maintenance catch-up.

12-Month severity forecast
No violation 70.3%
Moderate concern 18.7%
Severe concern 11.0%
Estimated probability of receiving a DBI Notice of Violation in the next 12 months at each severity level. Model: full_hgb_balanced.
Apartment reviews

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The story over time

638-642 Hayes St event timeline

Violations, complaints, fire incidents, permits, and buyouts — most recent records in order.

2026
311 Request Jan 22
Garbage and debris
other loose garbage debris yard waste

See all 2 events

Full history back to 2024 — violations, complaints, permits, buyouts, and fire incidents.

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Every record we have

Full data for 638-642 Hayes St apartments

13 SF public datasets for this parcel — permits, violations, complaints, fire records, 311 calls, planning records, and buyouts.

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